Diamond controls epithelial polarity through the dynactin-dynein complex

Epithelial polarity is critical for proper functions of epithelial tissues, tumorigenesis, and metastasis. The evolutionarily conserved transmembrane protein Crumbs (Crb) is a key regulator of epithelial polarity. Both Crb protein and its transcripts are apically localized in epithelial cells. However, it remains not fully understood how they are targeted to the apical domain. Here, using Drosophila ovarian follicular epithelia as a model, we show that epithelial polarity is lost and Crb protein is absent in the apical domain in follicular cells (FCs) in the absence of Diamond (Dind). Interestingly, Dind is found to associate with different components of the dynactin-dynein complex through co-IP-MS analysis. Dind stabilizes dynactin and depletion of dynactin results in almost identical defects as those observed in dind-defective FCs. Finally, both Dind and dynactin are also required for the apical localization of crb transcripts in FCs. Thus our data illustrate that Dind functions through dynactin/dynein-mediated transport of both Crb protein and its transcripts to the apical domain to control epithelial apico-basal (A/B) polarity.

A feedforward loop between JAK/STAT downstream target p115 and STAT in germline stem cells

The maintenance of germline stem cells (GSCs) is essential for tissue homeostasis. JAK/STAT signaling maintains GSC fate in Drosophila testis. However, how JAK/STAT signaling maintains male GSC fate through its downstream targets remains poorly understood. Here, we identify p115, a tER/cis-Golgi golgin protein, as a putative downstream target of JAK/STAT signaling. p115 maintains GSC fate independent of GM130 and GRASP65. p115 localizes in cytosol, the ER and Golgi apparatus in germline cells and is required for the morphology of the ER and Golgi apparatus. Furthermore, depletion of p115 in GSCs results in aberrant spindle orientation. Mechanistically, p115 associates with and stabilizes STAT. Finally, ectopic expression of STAT completely restores GSC loss caused by p115 depletion. Collectively, JAK/STAT signaling and p115 form a feedforward loop to maintain male GSC fate. Our work provides new insights into the regulatory mechanism of how stem cell maintenance is properly controlled by JAK/STAT signaling.

Novel intrinsic factor Yun maintains female germline stem cell fate through Thickveins

Germline stem cells (GSCs) are critical for the reproduction of an organism. The self-renewal and differentiation of GSCs must be tightly controlled to avoid uncontrolled stem cell proliferation or premature stem cell differentiation. However, how the self-renewal and differentiation of GSCs are properly controlled is not fully understood. Here, we find that the novel intrinsic factor Yun is required for female GSC maintenance in Drosophila. GSCs undergo precocious differentiation due to de-repression of differentiation factor Bam by defective BMP/Dpp signaling in the absence of yun. Mechanistically, Yun associates with and stabilizes Thickveins (Tkv), the type I receptor of Dpp/BMP signaling. Finally, ectopic expression of a constitutively active Tkv (Tkv^QD) completely suppresses GSC loss caused by yun depletion. Collectively, these data demonstrate that Yun functions through Tkv to maintain GSC fate. Our results provide new insight into the regulatory mechanisms of how stem cell maintenance is properly controlled.

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Novel intrinsic factor Yun is required for female GSC maintenance

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Yun-defective GSCs undergo differentiation due to Bam upregulation

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Yun associates with and stabilizes Tkv to regulate GSC maintenance

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GSC loss in the absence of yun could be rescued by constitutively active Tkv

Phosphorylation of Yun is required for stem cell proliferation and tumorigenesis

Stem cells maintain adult tissue homeostasis under physiological conditions. Uncontrolled stem cell proliferation will lead to tumorigenesis. How stem cell proliferation is precisely controlled is still not fully understood. Phosphorylation of Yun is essential for ISC proliferation. Yun is essential for the proliferation of normal and transformed intestinal stem cells. Our mass spectrometry and biochemical data suggest that Yun can be phosphorylated at multiple residues in vivo. Interestingly, we show that the phosphorylation among these residues is likely interdependent. Furthermore, phosphorylation of each residue in Yun is important for its function in ISC proliferation regulation. Thus, our study unveils the important role of post-translational modification of Yun in stem cell proliferation.

Auxilin regulates intestinal stem cell proliferation through EGFR

Adult tissue homeostasis is maintained by residential stem cells. The proliferation and differentiation of adult stem cells must be tightly balanced to avoid excessive proliferation or premature differentiation. However, how stem cell proliferation is properly controlled remains elusive. Here, we find that auxilin (Aux) restricts intestinal stem cell (ISC) proliferation mainly through EGFR signaling. aux depletion leads to excessive ISC proliferation and midgut homeostasis disruption, which is unlikely caused by defective Notch signaling. Aux is expressed in multiple types of intestinal cells. Interestingly, aux depletion causes a dramatic increase in EGFR signaling, with a strong accumulation of EGFR at the plasma membrane and an increased expression of EGFR ligands in response to tissue stress. Furthermore, Aux co-localizes and associates with EGFR. Finally, blocking EGFR signaling completely suppresses the defects caused by aux depletion. Together, these data demonstrate that Aux mainly safeguards EGFR activation to keep a proper ISC proliferation rate to maintain midgut homeostasis.

Identification of a new allele of O-fucosyltransferase 1 involved in Drosophila intestinal stem cell regulation

Adult stem cells are critical for the maintenance of tissue homeostasis. However, how the proliferation and differentiation of intestinal stem cells (ISCs) are regulated remains not fully understood. Here, we find a mutant, stum 9-3, affecting the proliferation and differentiation of Drosophila adult ISCs in a forward genetic screen for factors regulating the proliferation and differentiation ISCs. stum 9-3 acts through the conserved Notch signaling pathway, upstream of the S2 cleavage of the Notch receptor. Interestingly, the phenotype of stum 9-3 mutant is not caused by disruption of stumble (stum), where the p-element is inserted. Detailed mapping, rescue experiments and mutant characterization show that stum 9-3 is a new allele of O-fucosyltransferase 1 (O-fut1). Our results indicate that unexpected mutants with interesting phenotype could be recovered in forward genetic screens using known p-element insertion stocks.

Summary: A mutant, stum 9-3, affecting the proliferation and differentiation of Drosophila adult intestinal stem cells (ISCs) was identified in a forward genetic screen for factors regulating the proliferation and differentiation ISCs. stum 9-3 acts through the Notch signaling pathway. Detailed mapping, rescue experiments and characterization show that stum 9-3 is not a stumble mutant where the p-element is inserted, but a new allele of O-fucosyltransferase 1 (O-fut1).

dRTEL1 is essential for the maintenance of Drosophila male germline stem cells

Stem cells have the potential to maintain undifferentiated state and differentiate into specialized cell types. Despite numerous progress has been achieved in understanding stem cell self-renewal and differentiation, many fundamental questions remain unanswered. In this study, we identify dRTEL1, the Drosophila homolog of Regulator of Telomere Elongation Helicase 1, as a novel regulator of male germline stem cells (GSCs). Our genome-wide transcriptome analysis and ChIP-Seq results suggest that dRTEL1 affects a set of candidate genes required for GSC maintenance, likely independent of its role in DNA repair. Furthermore, dRTEL1 prevents DNA damage-induced checkpoint activation in GSCs. Finally, dRTEL1 functions to sustain Stat92E protein levels, the key player in GSC maintenance. Together, our findings reveal an intrinsic role of the DNA helicase dRTEL1 in maintaining male GSC and provide insight into the function of dRTEL1.

Derlin-1 and TER94/VCP/p97 are required for intestinal homeostasis

Adult stem cells are critical for the maintenance of residential tissue homeostasis and functions. However, the roles of cellular protein homeostasis maintenance in stem cell proliferation and tissue homeostasis are not fully understood. Here, we find that Derlin-1 and TER94/VCP/p97, components of the ER-associated degradation (ERAD) pathway, restrain intestinal stem cell proliferation to maintain intestinal homeostasis in adult Drosophila. Depleting any of them results in increased stem cell proliferation and midgut homeostasis disruption. Derlin-1 is specifically expressed in the ER of progenitors and its C-terminus is required for its function. Interestingly, we find that increased stem cell proliferation is resulted from elevated ROS levels and activated JNK signaling in Derlin-1- or TER94-deficient progenitors. Further removal of ROS or inhibition of JNK signaling almost completely suppressed increased stem cell proliferation. Together, these data demonstrate that the ERAD pathway is critical for stem cell proliferation and tissue homeostasis. Thus we provide insights into our understanding of the mechanisms underlying cellular protein homeostasis maintenance (ER protein quality control) in tissue homeostasis and tumor development.

Autophagy induction in tumor surrounding cells promotes tumor growth in adult Drosophila intestines

During tumorigenesis, tumor cells interact intimately with their surrounding cells (microenvironment) for their growth and progression. However, the roles of tumor microenvironment in tumor development and progression are not fully understood. Here, using an established benign tumor model in adult Drosophila intestines, we find that non-cell autonomous autophagy (NAA) is induced in tumor surrounding neighbor cells. Tumor growth can be significantly suppressed by genetic ablation of autophagy induction in tumor neighboring cells, indicating that tumor neighboring cells act as tumor microenvironment to promote tumor growth. Autophagy in tumor neighboring cells is induced downstream of elevated ROS and activated JNK signaling in tumor cells. Interestingly, we find that active transport of nutrients, such as amino acids, from tumor neighboring cells sustains tumor growth, and increasing nutrient availability could significantly restore tumor growth. Together, these data demonstrate that tumor cells take advantage of their surrounding normal neighbor cells as nutrient sources through NAA to meet their high metabolic demand for growth and progression. Thus we provide insights into our understanding of the mechanisms underlying the interaction between tumor cells and their microenvironment in tumor development.

[Four-steps surgery for infected pancreatic necrosis based on "Step-up" strategy: a retrospective study]

Objective: To examine the effect of the "four-steps" treatment on infectious pancreatic necrosis(IPN). Methods: The data of 207 patients who were diagnosed with IPN from January 2013 to December 2017 at Department of Pancreaticobiliary Surgery, the First Affiliated Hospital of Harbin Medical University were analyzed retrospectively. Among 207 patients, 132(63.8%) were males and 75(36.2%) were females. The median age was 45 years old (range: 19 to 80 years old). One hundred and fifty-eight patients(76.3%) suffered severe acute pancreatitis and 49 patients(23.7%) suffered moderately severe acute pancreatitis. Percutaneous catheter drainage(PCD) was performed on all the patients(Step 1). Patients received "four-steps" minimally invasive treatment strategy in step-up group(173 patients). The following steps after PCD were mini-incision access pancreatic necrosectomy(MIAPN) (Step 2), sinus tract endoscopic debridement and(or) PCD for residual infections(Step 3) and finally conventional open pancreatic necrosectomy(OPN) (Step 4). Patients(34 cases) received conventional open pancreatic necrosectomy after invalided PCD in OPN group. The perioperative parameters and prognosis were compared between Step-up group and OPN group. Normally distributed quantitative variables were analyzed by t-test, non-normally distributed quantitative variables were analyzed by Wilcoxon chi-square test and categorical variables were analyzed by χ(2) test or Fisher exact test, respectively. Results: The basic characteristics of the two groups of patients were similar, but the referral rate of patients and the rate of preoperative 3 days organ failure in the OPN group were significantly higher than those of step-up group patients(47.1% vs. 28.9%, χ(2)=4.313, P=0.038; 26.5% vs. 9.2%, χ(2)=2.819, P=0.011). The frequency of PCD and the number of PCD tube (root) were less than those in the step-up group(1(1) vs. 2(1), Z=-3.373, P=0.018; 2(1) vs. 3(2), Z=-2.208, P=0.027). Compared with the OPN group, the interval time from onset to surgery and the MIAPN operation time were significantly shorter in the step-up group(29(15) days vs. 36(17)days, Z=-0.567, P=0.008; 58(27)minutes vs. 90(56)minutes, Z=-3.908, P<0.01); postoperative mortality was lower(5.8% vs.17.6%, χ(2)=4.070, P=0.044); the overall incidence of postoperative complications was reduced(23.1% vs. 55.9%, χ(2)=14.960, P<0.01) and the incidence of new-onset organ failure was decreased after operation in the step-up group(37.5% vs.47.4%, χ(2)=7.133, P=0.007). The incidence of local abdominal complications (pancreatic fistula, intra-abdominal hemorrhage, gastrointestinal fistula) showed no significant difference between the two groups (P>0.05). Fewer patients required ICU treatment after operation in the step-up group compared with OPN group(22.0% vs. 44.1%, χ(2)=6.204, P=0.013). Patients in the Step-up group has shorter hospital stay than patients in OPN group (46(13) days vs. 52(13)days, Z=-1.993, P=0.046). Conclusions: The clinical effects of "four-steps" exhibited the superiority of minimally invasive treatment of IPN.And MIAPN is a simple, safe and effective procedure to remove pancreatic necrotic tissue and decrease complications.

Heparan sulfate maintains adult midgut homeostasis in Drosophila

Tissue homeostasis is controlled by the differentiated progeny of residential progenitors (stem cells). Adult stem cells constantly adjust their proliferation/differentiation rates to respond to tissue damage and stresses. However, how differentiated cells maintain tissue homeostasis remains unclear. Here, we find that heparan sulfate (HS), a class of glycosaminoglycan (GAG) chains, protects differentiated cells from loss to maintain intestinal homeostasis. HS depletion in enterocytes (ECs) leads to intestinal homeostasis disruption, with accumulation of intestinal stem cell (ISC)-like cells and mis-differentiated progeny. HS-deficient ECs are prone to cell death/stress and induced cytokine and epidermal growth factor (EGF) expression, which, in turn, promote ISC proliferation and differentiation. Interestingly, HS depletion in ECs results in the inactivation of decapentaplegic (Dpp) signaling. Moreover, ectopic Dpp signaling completely rescued the defects caused by HS depletion. Together, our data demonstrate that HS is required for Dpp signal activation in ECs, thereby protecting ECs from ablation to maintain midgut homeostasis. Our data shed light into the regulatory mechanisms of how differentiated cells contribute to tissue homeostasis maintenance.

Heparan sulfate negatively regulates intestinal stem cell proliferation in Drosophila adult midgut

Tissue homeostasis is maintained by differentiated progeny of residential stem cells. Both extrinsic signals and intrinsic factors play critical roles in the proliferation and differentiation of adult intestinal stem cells (ISCs). However, how extrinsic signals are transduced into ISCs still remains unclear. Here, we find that heparan sulfate (HS), a class of glycosaminoglycan (GAG) chains, negatively regulates progenitor proliferation and differentiation to maintain midgut homeostasis under physiological conditions. Interestingly, HS depletion in progenitors results in inactivation of Decapentaplegic (Dpp) signaling. Dpp signal inactivation in progenitors resembles HS-deficient intestines. Ectopic Dpp signaling completely rescued the defects caused by HS depletion. Taken together, these data demonstrate that HS is required for Dpp signaling to maintain midgut homeostasis. Our results provide insight into the regulatory mechanisms of how extrinsic signals are transduced into stem cells to regulate their proliferation and differentiation.

Age, lifestyle and self-perceptions of hair: Is there an association with hair diameter and tensile properties?

OBJECTIVE

To determine the association of age, lifestyle habits and the self-perception of hair condition with the objectively measured physical properties of hair in Caucasian females with brown hair.

METHODS

Hair biophysical properties, lifestyle habits data and self-perceptions of hair condition were collected on 110 Caucasian females with brown hair ranging in age from 17 to 78. Hair diameter (cross-sectional area) and tensile properties (elastic modulus, break strength and break extension) were measured at the root end of individual fibres (n = 100/subject) from the crown and frontal regions using objective instrumental methods. Other measures included body mass index (BMI) and Savin female pattern hair loss grades based on judging of standardized front, top and side view head images. Lifestyle habits and practices and self-perceived hair condition were obtained via a standardized self-assessment questionnaire.

RESULTS

Hair fibre diameter and break extension decreased significantly with age. Hair fibre elastic modulus and Savin hair loss scores increased significantly with age. No age-related change in hair fibre break stress was observed. A history of smoking or being overweight was significantly associated with having lower hair fibre cross-sectional area but was not associated with any of the measured tensile properties. Subjects who perceived their hair as fine, thinning or weak had significantly lower cross-sectional areas than subjects who did not. Subjects who perceived their hair to be healthy or strong had significantly higher cross-sectional areas than subjects who did not.

CONCLUSION

The biophysical properties of hair change significantly with age. A history of smoking or being overweight was significantly associated with having smaller hair cross-sectional area but was not associated with differences in hair tensile properties. The self-perception of having strong or healthy hair seems more associated with having a larger cross-sectional area than any real differences in hair strength.Abstrait.

[Clinical analysis of small incision minimally invasive approach in treatment of infected pancreatic necrosis]

Objective: To investigate the safety and efficiency of small incision minimally invasive approach pancreatic necrosectomy in the treatment of infected pancreatic necrosis. Methods: The data of 164 patients who underwent small incision minimally invasive approach pancreatic necrosectomy for infected pancreatic necrosis at Department of Pancreatic and Biliary Surgery, the First Affiliated Hospital of Harbin Medical University from January 2012 to December 2016 were analyzed retrospectively.Among 164 patients, there were 102 male and 62 female patients.The median age was 46 years(ranging from 19 to 79 years). One hundred and one patients(61.6%) suffered from severe acute pancreatitis and 63 patients(38.4%) suffered from moderately severe acute pancreatitis.Following step-up approach principle, the surgical procedures were performed for 131 patients(79.9%) who suffered from sepsis which could not be alleviated via percutaneous catheter drainage(PCD). The other 33 patients(20.1%) who did not undergo PCD directly took small incision minimally invasive approach pancreatic necrosectomy.Preoperative CT images were used to determine the location of the lesion.The PCD puncture points or the points where the abscess was closest to the skin were chosen as the incision.Gradually, the small incision minimally invasive approach pancreatic necrosectomy were performed via cutting all layers into the abscess. Results: The median time from the onset of symptom to first operation was 32 days(ranging from 23 to 45 days). The average hospital stay was 46 days(ranging from 29 to 103 days). The average number of drainage tubes placed was 4 pieces(ranging from 2 to 8 pieces). Ninety-two patients(56.0%) underwent minimal access retroperitoneal pancreatic necrosectomy. Thirty-six patients(22.0%) underwent minimal invasive approach lesser omentum sac pancreatic necrosectomy.Thirty-six patients(22.0%) underwent minimal invasive approach lesser omentum sac pancreatic necrosectomy combined with minimal access retroperitoneal pancreatic necrosectomy.A total of 148 cases(90.2%) were cured via minimally invasive approach pancreatic necrosectomy, 8 cases(4.9%) were cured after transfering to open pancreatic necrosectomy.The cure rate was 95.1%(156/164). The mainly postoperative complications included pancreatic fistula(25 cases), intra-abdominal hemorrhage(10 cases), gastric fistula (2 cases), duodenal fistula(4 cases) and colonic fistula(3 cases). The overall incidence rate of complications was 26.8%(44/164). Eight cases were dead after surgery and the in-hospital mortality was 4.9%(8/164). Conclusion: In summary, small incision minimally invasive approach pancreatic necrosectomy is an effective way to clean up necrotic tissue, improve the drainage, reduce complications in dealing with infected pancreatic necrosis.

[Advances in diagnosis and treatment of undifferentiated pancreatic carcinoma with osteoclast-like giant cells]

Undifferentiated pancreatic carcinoma with osteoclast-like giant cell(UOC) published to date, and most have been in Asia, is a rare occurrence making up 1% of all pancreatic malignancies.With the increasing number of reported cases of the disease, the degree of awareness of the disease also gradually deepened, but there are few summary articles for the clinical features, imaging features, pathological features, treatment programs, prognosis and other aspects of UOC.Hence, this article is going to introduce pathological features, clinical manifestations, diagnosis and treatment of adjuvant advances of UOC in detail.

[Minimally invasive small incision direct anterior total hip arthroplasty in the lateral decubitus position: complications and early outcome]

Objective: To analyze the feasibility, perioperative complications and early outcomes of minimally invasive small incision in direct anterior approach total hip arthroplasty in lateral decubitus position. Methods: From January 2015 to January 2017, 212 patients (228 hips) received minimally invasive small incision (approximately 8 cm in length) direct anterior approach total hip arthroplasty in modified lateral decubitus position and approach. Sixteen cases underwent bilateral hip arthroplasty separately. All procedures were performed by the same surgeon in the Department of Orthopedics, the First Affiliated Hospital of University of Science and Technology of China, Anhui Provincial Hospital. Twenty-eight patients (28 hips) were set as the complicated case group. The rest 184 patients (200 hips) had no previous hip surgeries, severe deformity and limited motion of the hip, were set as the standard group, and were divided into the first 100 cases group and the second 100 cases group in sequence. The difference between the standard group and complicated case group were analyzed. Also we compared the difference between the first 100 cases and the second 100 cases. Perioperative complications, postoperative function and radiological evaluation were recorded and statistically analyzed. The t test was applied to compare the data between groups. Results: All the patients were followed-up for 13 to 25 months[(18±5) months]. Intraoperative complications and postoperative complications happened in 9 and 34 patients respectively. The anterior dislocation occurred in 2 cases. The standard group showed significant superior outcomes when compared with complicated case group in the surgical time[(42±19) vs (67±16) min, t=-2.628, P=0.027], blood loss[(222±94) vs (579±120) ml, t=-8.371, P=0.000], postoperative Harris hip score[90±5 vs 83±7, t=2.390, P=0.024]and the rate of surgical complication (15.0% vs 46.4%, χ(2)=15.854, P=0.000). The complication rate tended to decrease in the second 100 cases when compared with that in the first 100 cases (11.0% vs 19.0%, χ(2)=3.922, P=0.037). Meanwhile, the second 100 cases showed significant excellent outcomes when compared with the first 100 cases in the mean surgical time[(34±15) vs (48±10) min, t=4.217, P=0.002]and blood loss[(182±52) vs (254±40) ml, t=2.889, P=0.018]. Conclusions: It suggests that there is a learning curve with the minimally invasive small incision direct anterior approach total hip arthroplasty in lateral decubitus position. The risk of intraoperative femoral fractures is slightly high, especially for cases with osteoporosis, stiffness and limited range of movement. Surgeons in early learning curve period should grasp the surgical indications and master the technical points.

Self-restrained regulation of stem cell niche activity by niche components in the Drosophila testis

Most, if not all, stem cells reside in a defined microenvironment, called the niche. Short-ranged niche signal must be tightly controlled to be active only inside the niche to maintain the proper balance of stem cell self-renewal verse differentiation. However, how niche components restrict localized niche signal activation remains largely unknown. Here, we find that Thickveins (Tkv, a type I receptor of the Dpp signaling pathway) in cyst stem cells (CySCs) of the testis niche prevents Dpp signaling activation outside of the niche. We show that Tkv functions as Dpp trap/sink to spatially restrain Dpp signaling inside the niche. This self-restrained regulation of niche activity by Tkv in CySCs is independent of the canonical Dpp signaling pathway. Our data demonstrate the critical roles of niche components (CySCs) in the self-restrained regulation of niche activity, which could be shed light on niche activity regulation in general.

[Research advances in anatomical study on the diffusion routs of acute pancreatitis]

The retroperitoneum space comprises anterior pararenal space, perirenal space and posterior pararenal space. Pancreas is a retroperitoneal organ and located in the anterior pararenal space of the retroperitoneum. Left and right sides anterior pararenal space are potentially communicated, which contains many adipose tissues and a little connective tissues. The exacerbation of acute pancreatitis results in the lesion spreading into adjacent area of pancreas in the retroperitoneal space. In addition, the lesion could spread into bare area of stomach, posterior colonic region, subperitoneal space and pelvic retroperitoneal space through the same anatomical space or communicating space. Due to the fascia destruction by pancreatic enzymes or the lesion directly diffuse through the weak fascia, the lesion could also diffuse across fascia to perirenal space, posterior pararenal space, the peritoneal cavity and abdominal wall. Finally, a series of complications are developed. The diffusion paths of acute pancreatitis are complex and diverse. Familiarity with these diffusion paths is useful for determining the severity and guiding therapy.

75 Improvement of Developmental Competence of Bovine In Vitro-Produced Embryos by Using Charcoal:Dextran-Stripped Fetal Bovine Serum on In Vitro Culture Media

Serum has widely been used as a main supplement to embryo in vitro culture media as it contains embryotrophic factors. Charcoal:dextran treatment of fetal bovine serum (FBS) removes lipophilic chemicals and certain steroid hormones and growth factors. The objective of this study was to investigate the effects of charcoal:dextran-stripped fetal bovine serum (CDS FBS) and heat-inactivated FBS (HI FBS) in embryo culture medium (SOF-BE1 medium supplemented with 10% of serum) on their ability to support in vitro development of bovine embryos. The developmental ability and quality of bovine embryos were determined by assessing their cell number, lipid content, mitochondrial activity, gene expression, and cryo-tolerance. The experiment was conducted in 6 replicates (350 oocytes per group). The differences in embryo development, integrated optical intensity, and expression levels of the various genes between experimental groups were analysed by one-way ANOVA. Duncan’s multiple range tests were used to test the differences between the treatments. The level of statistical significance was set at P < 0.05. The percentages of embryos that underwent cleavage and formed a blastocyst were significantly (P < 0.05) higher in medium containing CDS FBS than in medium containing HI FBS (42.84 ± 0.78% v. 36.85 ± 0.89%, respectively). The total number of cells per Day 8 blastocyst was not significantly different (P > 0.05) between the CDS FBS group (208.40 ± 14.77) and the HI FBS group (195.11 ± 19.15). Furthermore, the beneficial effects of CDS FBS on embryos were associated with a significantly increased mitochondrial activity, as identified by MitoTracker Green, and reduced intracellular lipid content, as identified by Nile red staining, which increased their cryo-tolerance. The post-thaw survival rate of blastocysts was significantly (P < 0.05) higher after 24 h in the CDS FBS than in the HI FBS group (85.33 ± 4.84% v. 68.67 ± 1.20%). Quantitative reverse transcription PCR showed that the mRNA levels of lipid metabolism-related genes, acyl-CoA synthetase long-chain family member 3, acyl-coenzyme A dehydrogenase long-chain, and the cholesterol metabolism related gene hydroxymethylglutaryl-CoA reductase were significantly increased upon culture with CDS FBS. Moreover, the mRNA levels of survival gene sirtuin 1, antioxidant gene superoxide dismutase 2, and anti-apoptotic associated gene B-cell lymphoma 2 in frozen–thawed blastocysts were significantly (P < 0.05) higher in the CDS FBS group than in the HI FBS group; however, the mRNA level of the pro-apoptotic gene BCL2-associated X protein was significantly reduced. In conclusion, these data suggest that supplementation of in vitro culture medium with CDS FBS improves in vitro bovine embryo developmental competence and the quality of blastocysts in terms of their crytolerance and gene expression. This research was supported by grant from the Next-Generation BiogGeen21 (No. PJ01107703), IPET (No. 315017-5 and 117029-3), Allergy free cat (Co.. Felix Pets), BK21plus, and KGSP.

The significance of HBD-3 and fluorescent composite carriers in the processof bone formation in rats infected with Staphylococcus aureus

OBJECTIVE

The objective of the present study was to explore the significance of human β-defensin 3 (HBD-3) through establishment and evaluation of the model of implant-related biofilm infection of the femoral condyle of the outer knee using Sprague-Dawley (SD) rats.

MATERIALS AND METHODS

Age-matched SD rats were divided into three groups, the HBD-3 group, HBD-3 fluorescent liposome group, and the HBD-3 liposome-microbubble fluorescent composite carrier group. After biofilm infection for 24 h, the fluorescent composite vector was injected intraperitoneally 2 times/day. After the first injection, rats in each group were sacrificed on the 7th, 14th, and 28th day. The lower end of the femur bone was harvested after removing the surrounding soft tissue. H&E and immunohistochemical staining were applied and light microscopy was used for observation. Fluorescent markers including tetracycline and calcein were used to follow the formation of new bone in vivo. Undecalcified specimens were embedded in epoxy resin (thickness of roughly 150 m), and confocal microscopy was used for observation.

RESULTS

By assessing cell proliferation with cell counting kit-8, the proliferation ability of cells in the HBD-3 liposome-microbubble fluorescent composite carrier group was significantly increased compared with the other groups (p<0.05). qPCR was used to measure the levels of alkaline phosphatase (ALP), type I collagen, osteocalcin (OCN), osteopontin (OPN), and bone sialoprotein (BSP) in each group. The levels of these genes in the HBD-3 liposome-microbubble fluorescent composite carrier group were significantly higher than those in other groups (p<0.05).

CONCLUSIONS

The application of the HBD-3 liposome-microbubble fluorescent composite carrier can significantly promote osteogenesis in rats infected with Staphylococcus aureus, and increase the expression levels of ALP, type I collagen, OCN, OPN, and BSP.

[Clinical experience on the employment of the staged step-up approach in the treatment of local complications secondary to severe acute pancreatitis]

Objective: To explore the experience and prognostic factors associated with the employment of the step-up approach in the treatment of local complications secondary to severe acute pancreatitis (SAP). Methods: The clinical data of 279 patients admitted to the Department of Pancreatic and Biliary Surgery, First Affiliated Hospital of Harbin Medical University from January 2011 to December 2015, whose local complications secondary to SAP were treated in a staged step-up framework, were retrospectively analyzed.For patients with documented or suspected infected pancreatic necrosis or gastrointestinal tract obstruction, some non-surgical interventions were initialed with the aim of postponing the timing of surgery to the forth week from the onset of SAP.The first-step intervention was a percutaneous catheter drainage (PCD) under the guidance of ultrasound. A minimal access retroperitoneal pancreatic necrosectomy, representing the second-step intervention, was conducted when PCD had failed. Finally, an open necrosectomy (the third-step intervention) was immediately resorted to when all of previous minimal invasive interventions had failed.Normally distributed quantitative variables were analyzed by t-test, non-normally distributed quantitative variables were analyzed by Wilcoxon chi-square test and categorical variables were analyzed by χ² test or Fisher's exact test.A multivariable Logistic regression analytic model was established to figure out the prognostic factors that were independently associated with the requirement of debridement in addition to drainage procedure during the staged step-up framework of patients with local complications secondary to SAP. Results: The initial interventions in this series were performed at 12 d (9-22 d) from the on-set of SAP and 104 cases (37.3%) were cured with ultrasound guided PCD alone.There were 152 cases (54.5%) cured by debridement in addition to PCD with the time interval of 30 d (25 to 44 d) since the on-set of the disease.The overall incidence of postoperative complications was 22.6% (63 cases) and in-hospital mortality was 8.2% (23 cases) in the present series.Multiple organ failures(MOF)(P<0.01, OR=3.15), heterogeneous collections (P<0.01, OR=2.40) and tertiary transfer (P=0.03, OR=1.80) were verified as the prognostic factors that were independently associated with the requirement of debridement in addition to PCD during the staged step-up framework of patients with local complications secondary to SAP. Conclusions: The staged step-up framework is a promising innovation that complies well with the era of minimal invasive surgery and is optimally suitable for the surgical interventions against SAP.MOF, heterogeneous collections and tertiary transfer are the prognostic factors that are independently associated with the requirement of debridement in addition to PCD during the staged step-up framework of patients with local complications secondary to SAP.

SP1-induced upregulation of the long noncoding RNA TINCR regulates cell proliferation and apoptosis by affecting KLF2 mRNA stability in gastric cancer

The long noncoding RNA TINCR shows aberrant expression in human squamous carcinomas. However, its expression and function in gastric cancer remain unclear. We report that TINCR is strongly upregulated in human gastric carcinoma (GC), where it was found to contribute to oncogenesis and cancer progression. We also revealed that TINCR overexpression is induced by nuclear transcription factor SP1. Silencing TINCR expression inhibited cell proliferation, colony formation, tumorigenicity and apoptosis promotion, whereas TINCR overexpression promoted cell growth, as documented in the SGC7901 and BGC823 cell lines. Mechanistic analyses indicated that TINCR could bind to STAU1 (staufen1) protein, and influence KLF2 mRNA stability and expression, then KLF2 regulated cyclin-dependent kinase genes CDKN1A/P21 and CDKN2B/P15 transcription and expression, thereby affecting the proliferation and apoptosis of GC cells. Together, our findings suggest that TINCR contributes to the oncogenic potential of GC and may constitute a potential therapeutic target in this disease.

EZH2-mediated epigenetic suppression of long noncoding RNA SPRY4-IT1 promotes NSCLC cell proliferation and metastasis by affecting the epithelial-mesenchymal transition

Recent evidence indicates that long noncoding RNAs (lncRNAs) have a critical role in the regulation of cellular processes such as differentiation, proliferation, and metastasis. These lncRNAs are dysregulated in a variety of cancers and many function as tumor suppressors; however, the regulatory factors involved in silencing lncRNA transcription are poorly understood. In this study, we showed that epigenetic silencing of lncRNA SPRY4 intronic transcript 1 (SPRY4-IT1) occurs in non-small-cell lung cancer (NSCLC) cells through direct transcriptional repression mediated by the Polycomb group protein enhancer of zeste homolog 2 (EZH2). SPRY4-IT1 is derived from an intron within SPRY4, and is upregulated in melanoma cells; knockdown of its expression leads to cell growth arrest, invasion inhibition, and elevated rates of apoptosis. Upon depletion of EZH2 by RNA interference, SPRY4-IT1 expression was restored, and transfection of SPRY4-IT1 into NSCLC cells resulted in a significant antitumoral effect, both in culture and in xenografted nude mice. Moreover, overexpression of SPRY4-IT1 was found to have a key role in the epithelial-mesenchymal transition through the regulation of E-cadherin and vimentin expression. In EZH2-knockdown cells, which characteristically showed impaired cell proliferation and metastasis, the induction of SPRY4-IT1 depletion partially rescued the oncogenic phenotype, suggesting that SPRY4-IT1 repression has an important role in EZH2 oncogenesis. Of most relevance, translation of these findings into human NSCLC tissue samples demonstrated that patients with low levels of SPRY4-IT1 expression had a shorter overall survival time, suggesting that SPRY4-IT1 could be a biomarker for poor prognosis of NSCLC.

Peptides design based on the interfacial helix of integrase dimer

HIV-I integrase (IN) plays a crucial role in the retroviral life cycle. The peptides derived from the helix of IN were reported to have the potency of inhibition. We designed a series of peptides based on interface helices alpha1 and alpha5 with the aim of increasing their inhibitory activity. The helix-forming tendency and the affinity with IN were essential for interfacial peptide inhibitors. The MD simulation and AGADIR prediction both showed favorable results for the designed peptides. The binding mode and binding free energy of peptide and IN were investigated subsequently to test our design. The improvement in binding free energy compared with that of alpha1 and alpha5 indicates that some of the designed peptides may have a higher potency for inhibiting the dimerization of IN. This study provides some useful information for rational design of IN peptide inhibitor.

Infrared microspectroscopy combined with conventional atomic force microscopy

This paper reports nanotopography and mid infrared (IR) microspectroscopic imaging coupled within the same atomic force microscope (AFM). The reported advances are enabled by using a bimaterial microcantilever, conventionally used for standard AFM imaging, as a detector of monochromatic IR light. IR light intensity is recorded as thermomechanical bending of the cantilever measured upon illumination with intensity-modulated, narrowband radiation. The cantilever bending is then correlated with the sample's IR absorption. Spatial resolution was characterized by imaging a USAF 1951 optical resolution target made of SU-8 photoresist. The spatial resolution of the AFM topography measurement was a few nanometers as expected, while the spatial resolution of the IR measurement was 24.4 μm using relatively coarse spectral resolution (25-125 cm(-1)). In addition to well-controlled samples demonstrating the spatial and spectral properties of the setup, we used the method to map engineered skin and three-dimensional cell culture samples. This research combines modest IR imaging capabilities with the exceptional topographical imaging of conventional AFM to provide advantages of both in a facile manner.

A peptide derived from hepatitis C virus E2 envelope protein inhibits a post-binding step in HCV entry

The HCV envelope proteins E1 and E2 are required for virus binding to cellular receptors and pH-dependent fusion with endosomal membranes. Envelope protein interactions within this multistep process may provide novel targets for development of antiviral agents. To identify E1 and E2 regions involved in critical steps of HCV entry, we screened an E1E2 overlapping peptide library for inhibition of infection using a lentiviral reporter vector pseudotyped with E1E2 envelope proteins. A 16-residue polypeptide containing a portion of the E2 transmembrane domain (Peptide 75) inhibited HCV pseudoparticle infection with an IC50 of approximately 0.3microM and did not inhibit infection by VSV-g pseudoparticles at concentrations up to 50microM. Structure-activity analysis of Peptide 75 showed that antiviral activity was dependent upon L-configuration and hydrophobic character, and that the native sequence was required for maximal activity. Peptide 75 did not show virocidal activity against HCV pseudoparticles or other viruses. Temperature-shift experiments showed that the peptide acted at a post-binding step and that inhibition was further increased when used in combination with an anti-CD81 antibody previously shown to inhibit pseudoparticle entry at a post-binding step. These data suggest that interactions involving the C terminal region of E2 may play an important role in the HCV entry process.

SCH 503034, a mechanism-based inhibitor of hepatitis C virus NS3 protease, suppresses polyprotein maturation and enhances the antiviral activity of alpha interferon in replicon cells

Cleavage of the hepatitis C virus (HCV) polyprotein by the viral NS3 protease releases functional viral proteins essential for viral replication. Recent studies by Foy and coworkers strongly suggest that NS3-mediated cleavage of host factors may abrogate cellular response to alpha interferon (IFN-alpha) (E. Foy, K. Li, R. Sumpter, Jr., Y.-M. Loo, C. L. Johnson, C. Wang, P. M. Fish, M. Yoneyama, T. Fujita, S. M. Lemon, and M. Gale, Jr., Proc. Natl. Acad. Sci. USA 102:2986-2991, 2005, and E. Foy, K. Li, C. Wang, R. Sumpter, Jr., M. Ikeda, S. M. Lemon, and M. Gale, Jr., Science 300:1145-1148, 2003). Blockage of NS3 protease activity therefore is expected to inhibit HCV replication by both direct suppression of viral protein production as well as by restoring host responsiveness to IFN. Using structure-assisted design, a ketoamide inhibitor, SCH 503034, was generated which demonstrated potent (overall inhibition constant, 14 nM) time-dependent inhibition of the NS3 protease in cell-free enzyme assays as well as robust in vitro activity in the HCV replicon system, as monitored by immunofluorescence and real-time PCR analysis. Continuous exposure of replicon-bearing cell lines to six times the 90% effective concentration of SCH 503034 for 15 days resulted in a greater than 4-log reduction in replicon RNA. The combination of SCH 503034 with IFN was more effective in suppressing replicon synthesis than either compound alone, supporting the suggestion of Foy and coworkers that combinations of IFN with protease inhibitors would lead to enhanced therapeutic efficacy.

[Effects of 18 alpha-glycyrrhizic acid on rat liver cytochrome P450 isoenzymes and phase II transferase]

AIM

To study the effect of 18 alpha-glycyrrhizic acid (18 alpha-GL) on hepatic microsomal drug metabolizing enzymes in rats.

METHODS

18 alpha-GL (12.5, 50.0 mg.kg-1.d-1) were given i.p. to male Wistar rats for 3, 6 or 12 consecutive days. The rats were sacrificed 24 h after the last dose and the liver microsomes were prepared for analysis of cytochrome P450 (CYP) isozymes and phase II transferase activites.

RESULTS

Aniline hydroxylase (CYP2E1) activities in the rats treated with 18 alpha-GL (12.5, 50.0 mg.kg-1) for 6 days decreased dose-dependently by up to 53.2%; For 3, 6 or 12 days 7-ethoxyresorufin O-deethylase (CYP1A1) activities in the rats of 50 mg.kg-1 dose group decreased time-dependently by 17.6%, 38.3% and 47.3%, respectively; Erythromycin N-demethylase (CYP3A) activities was significantly inhibited from 23.1% to 34.3%. UDP-glucuronosyltransferase activities toward 7-hydroxy-4-methylcoumarin significantly increased ranging from 19.3% to 29.9%. UDP-glucuronosyltransferase activities toward 4-phenylphenol in the rats treated with 18 alpha-GL (12.5, 50.0 mg.kg-1) for 6 days increased by 45.9% and 70.3%. Glutathione S-transferase (GST) activities in the rats treated with 18 alpha-GL (12.5, 50.0 mg.kg-1) for 6 days increased by 13.7% and 48.3% in dose-dependent manner.

CONCLUSION

18 alpha-GL inhibited rat liver microsomal cytochrome P450 while induced phase II transferase.

The role of apolipoprotein E in cognitive decline after cardiac operation

BACKGROUND

Recently, Tardiff and colleagues have suggested that the presence of the apolipoprotein E, epsilon4 allele was associated with increased likelihood of cognitive decline after coronary artery bypass grafting. The objective of the current study was to replicate this earlier work using an increased sample size. The increased sample also enabled an analysis by individual genotype in cognitive decline after coronary artery bypass grafting.

METHODS

Apolipoprotein E genotyping was performed on 111 individuals undergoing coronary artery bypass grafting. Each participant underwent a battery of nine neuropsychological tests before operation and 4 to 7 weeks after operation.

RESULTS

Cognitive decline, assessed by both continuous Z change scores and two categoric measures of cognitive deficit, was not significantly associated with either individual apolipoprotein E genotypes or categorization by the presence or absence of the epsilon4 allele. The examination of potential moderating factors did not alter this finding.

CONCLUSIONS

This study suggests that the epsilon4 allele is not associated with cognitive decline in the weeks after coronary artery bypass grafting.

Analysis of expression of the binary toxin genes from Bacillus sphaericus in Anabaena and the potential in mosquito control

Anabaena strains expressing the binary toxin genes of Bacillus sphaericus produce high larvicidal activity with living cells. Western blot analysis showed that the 51-kDa and 42-kDa toxin proteins were stable in Anabaena. When a DNA fragment upstream of the 51-kDa protein gene was deleted, the toxicity was reduced by over a hundred-fold, whereas deletions at the coding regions showed that the cooperation of the two proteins expressed in Anabaena is essential for the larvicidal activity. Outdoor tests showed that the genetically altered Anabaena could keep containers with natural water from being inhabited by Culex larvae for over 2 months.

Cerebral microembolism detected by transcranial Doppler during cardiac procedures

BACKGROUND AND PURPOSE

Cerebral embolism with clinical sequelae may rarely complicate cardioversion and cardiac catheterization. Transcranial Doppler sonography has recently been introduced to monitor microemboli entering the middle cerebral artery in cardiac and carotid surgery. We therefore used this technique to evaluate the risk of asymptomatic embolism during common cardiac procedures.

METHODS

Patients were monitored by transcranial Doppler while undergoing direct current cardioversion (n=15) and cardiac catheterization (n=17).

RESULTS

Microemboli were detected in all patients having cardiac catheterization but in only 1 patient after cardioversion.

CONCLUSIONS

Microembolism occurred frequently during cardiac catheterization and rarely during cardioversion. It is not yet known whether this has clinical relevance.

A Streptomyces coelicolor antibiotic regulatory gene, absB, encodes an RNase III homolog

Streptomyces coelicolor produces four genetically and structurally distinct antibiotics in a growth-phase-dependent manner. S. coelicolor mutants globally deficient in antibiotic production (Abs(-) phenotype) have previously been isolated, and some of these were found to define the absB locus. In this study, we isolated absB-complementing DNA and show that it encodes the S. coelicolor homolog of RNase III (rnc). Several lines of evidence indicate that the absB mutant global defect in antibiotic synthesis is due to a deficiency in RNase III. In marker exchange experiments, the S. coelicolor rnc gene rescued absB mutants, restoring antibiotic production. Sequencing the DNA of absB mutants confirmed that the absB mutations lay in the rnc open reading frame. Constructed disruptions of rnc in both S. coelicolor 1501 and Streptomyces lividans 1326 caused an Abs(-) phenotype. An absB mutation caused accumulation of 30S rRNA precursors, as had previously been reported for E. coli rnc mutants. The absB gene is widely conserved in streptomycetes. We speculate on why an RNase III deficiency could globally affect the synthesis of antibiotics.

[Serum glutathione S-transferase activity as an early marker of thioacetimide-induced acute hepatotoxicity in mice]

The objective of this paper was to evaluate serum glutathione S-transferasethe (GST) in thioacetimide (TAA)-induced hepatotoxicity in mice. The results showed that intraperitoneal injection of TAA (25-100 mg/kg) increased serum GST activity. The activity of GST was dose- and time-related to TAA. There was a good positive correlation between serum GST and serum alanine transaminase(ALT) activities. The content of reduced glutathione(GSH) and activities of GST, glutathione peroxidase(GSH-Px) and superoxide dismutase(SOD) were significantly decreased while serum GST activity induced by TAA was high. The results suggested that the reduced hepatic antioxidative function is one of the mechanism of TAA-induced hepatotoxicity, and serum GST activity is a sensitive and early marker in detecting TAA-induced hepatotoxicity.

Demethylation capacity of human fetal adrenal mitochondrial cytochrome P-450 in vitro

AIM

To explore the capacity and characteristics of adrenal mitochondria to metabolize xenobiotics in vitro in human fetus.

METHODS

Subcellular fractions of fetal adrenal were prepared by differential centrifugation. Mitochondrial P-450 system was proved by spectral analyses and SDS-PAGE. The formaldehyde formation contents were measured with Nash reagent.

RESULTS

The erythromycin N-demethylation linearly increased in the protein concentration (1-4 mg)- and incubation time (10-30 min)-dependent manners. A typical concentration-effect relationship appeared with erythromycin 0.067-1 mmol.L-1 and a positive correlation (r = 0.641, P < 0.05) existed between erythromycin N-demethylation and gestation months. The N-demethylation values (nmol.s-1/g protein) of erythromycin (2.7 +/- 0.8), benzfetamine (1.1 +/- 0.5), and aminophenazone (0.9 +/- 0.4) in mitochondria were 89% (P > 0.05), 162% (P < 0.01), and 62% (P < 0.01), respectively, of those in microsomes. There was correlation between mitochondria and microsomes in the N-demethylation of erythromycin (r = 0.708, P < 0.05) and benzfetamine (r = 0.707, P < 0.05). Troleandomycin stimulated erythromycin N-demethylation in adrenal mitochondria as well as in adrenal and liver microsomes in vitro.

CONCLUSION

Fetal adrenal mitochondria, with multiple P-450 isoforms and greater capacity of demethylation, play a role in drug-metabolism during fetal development.

[Effect of allicin on ethanol-induced hepatotoxicity in mice]

To study the effect of allicin, an effective component of garlic, on ethanol-induced hepatotoxicity in mice. The results showed that allicin (10 mg/kg ig, qd x 10) could reverse the higher activities of serum ALT and glutathione s-transferase (GST) in ethanol-treated mice. Furthermore, allicin could significantly enhance the content of hepatic reduced glutathione (GSH), and the activities of hepatic glutathione peroxidase (GSH-Px), glutathione reductase (GSH-Re) and GST in ethanol-induced hepatotoxicity mice. There were no remarkable changes in the hepatic catalase (Cat) and superoxide dismutase(SOD) activities. These results suggested that allicin have the effective hepato-protection on ethanol-induced hepatotoxicity, which is related to its selective effect on the glutathione-related enzyme system.

[Correlation noise detection in encephaloblood-fluidity signal]

The aim of this study was to remove random white noise which mixes with encephaloblood fluidity signal. Based on the principles of correlation detection and a priori knowledge of encephaloblood fluidity, the authors adopted the coherent averaging method and obtained pure encephaloblood fluidity signal. The result of practical use has demonstrated that the more times the averaging progresses, the more distinctly the wave shows up.